• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1217-1220
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• 2007

The saprophytic fungus Ulocladium atrum Preuss is a promising biological control agent for Botrytis cinerea in greenhouse- and field-grown crops. However, despite its known potent antifungal activity, no antifungal substance has yet been reported. In an effort to characterize the antifungal substance from U. atrum, we isolated an antibiotic peptide. Based on extensive spectroscopic analyses, its structure was established as a cyclopeptolide with a high portion of N-methylated amino acids, and its $^1H$ and $^{13}C$ chemical shifts were completely assigned based on extensive 1D and 2D NMR experiments. Compound 1 exhibited potent antifungal activity against the plant pathogenic fungus Botrytis cinerea and moderate activity against Alternaria alternate and Magnaporthe grisea.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.13-18
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• 2014

Bacillus subtilis JW-1 was isolated from rhizosphere soil as a potential biocontrol agent of bacterial wilt caused by Ralstonia solanacearum. Seed treatment followed by a soil drench application with this strain resulted in >80% reduction in bacterial wilt disease compared with that in the untreated control under greenhouse conditions. The antibacterial compound produced by strain JW-1 was purified by bioactivity-guided fractionation. Based on mass spectroscopy and nuclear magnetic resonance spectral data ($^1H$, $^{13}C$, $^1H-^1H$ correlation spectroscopies, rotating frame nuclear Overhauser effect spectroscopy, and heteronuclear multiple-bond correlation spectroscopy), the structure of this compound was elucidated as a cyclic lipopeptide composed of a heptapeptide (Gln-Leu-Leu-Val-Asp-Leu-Leu) bonded to a ${\beta}$-hydroxy-iso-hexadecanoic acid arranged in a lactone ring system.

• Journal of environmental and Sanitary engineering
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• v.8 no.1
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• pp.129-138
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• 1993

The marked spread of the cockraches of recent years has raised a great social problem in urban areas. The cockroach have to remove1 because transmit a disease to human as pest insect, but particulars are not yet reported on biological control agent for the cockroach removal. This study was tried for the first time on biological control for the cockroach removal. The obtained results were as follows : 1. The isolated were spore-forming bacillus 1098 strain in soil. The No. 109(TH 109) strain of the among spore-forming bacillus was showed the poisonous against Cockroach. 2. The biological characteristics and flagella antigenicity of the strain is similar to Bacillus thur-ingiensis subsp. indiana. 3. TH 109 strain have the delta-endotoxin of cuboid shap. 4. This delta-endotoxin of product by TH 109 strain was toxic to the cockroach(Blattella gemzanica. L).

• Journal of Species Research
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• v.5 no.3
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• pp.477-482
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• 2016

Mite of the genus Hypoaspis of family Laelapidae are free-living soil predators mostly observed on the open grass field. Five species in the genus Hypoaspis were listed in Korean Catalog (NIBR, 2013) without detail information. Recent series of soil acarine biodiversity survey in Gyeongbuk and Gangwon provinces during 2009-2015 recovered a new record of Hypoaspis sardous (Canestrini, 1884) to Korean inventory from apple orchard and riparian grass land. Detailed description and morphological comparison with the related species, H. aculeifer which is well known biological control agent of horticultural crop pests were provided with identification keys.

• Microbiology and Biotechnology Letters
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• v.23 no.2
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• pp.243-248
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• 1995

Agrochemicals for the plant-disease control are criticized severely for causing environmental pollution and residual problems, and consequently microbial disease control agents are expected to be safer and more economical for sustainable agriculture. Treatment of biological control agents to seed requires the use of effective delivery systems that allow full expression of the benefical qualities of the bioprotectant. For the activation and establishment of bioprotectant around the plant seed which are able protect the seeds and seedlings from pathogen attack, the optimal liquid coating formulation was obtained using 2% sodium carboxymethyl cellulose (binder), 20% sesame dregs (solid particulate material), and dried spore of Bacillus subtilis YBL-7 (bioprotectants, 10 mg/g of seed). Suppressive of root rot was demonstrated in pot trials with coated kidney bean (Phaseolus vulgaris L.) seeds. Coated seeds with B. subtilis YBL-7 spore in F. solani-infested soil reduced disease incidence by 85% to 90% after 30 days.

• Journal of the Korean Society of Tobacco Science
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• v.15 no.1
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• pp.26-33
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• 1993

Effect of an avirulent bacteriocin-producing strain(ABPS) of Pseudomonas solanacearum adapted to low temperature on the control of tobacco bacterial wilt was examined under the natural field conditions. The ABPS of p. solanacearum were succeeding-cultured at gradually low temperature, 3$0^{\circ}C$ to 13$^{\circ}C$. The isolates adapted to low temperature grew faster than the wild type either in artificial media or on the tobacco rhizoplane. The control effect of one of the isolates on bacterial wilt was higher than that of the wild type when the bacterial suspension had been poured onto the tobacco rhizosphere soil on 1 day before and 15 days after transplanting to the field. It was suggested that ABPS of p. solanaceamm adapted to the low temperature, might be more effective biological control agent than the wild type.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.48-52
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• 2005

Six stains of plant growth promoting rhizobacteria were selected through germinating seed assay and root colonization assay. Among them, SKU-78 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 60% reduction of bacterial wilt disease compared with the control. It was suggested that SKU-78 strain activated the host defense systems in plants, based on lack of direct antibiosis against pathogen. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, SKU-78 stain was identified as Bacillus sp. SKU-78.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.370.1-370
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• 2001

• Journal of Applied Biological Chemistry
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• v.55 no.4
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• pp.247-252
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• 2012

This study examined the control effects of amino acid biochemical agent extracted from chicken feathers on Meloidogyne incognita for the purpose of developing an environmentally friendly nematicidal agent that can replace chemical control of root-knot nematodes (RKN). We investigated the lethal effects of J2 juveniles for 19 types of commercial amino acids. As a result, five kinds of amino acids (L-asparagine, L-aspartic acid, L-methionine, L-tyrosine, L-cysteine) showed mortality rate of more than 50% at a concentration of 50 mM. L-asparagine showed the highest mortality rate at 94%. We also investigated the lethal effect of J2 juveniles and suppressive effects of egg hatching by feather amino acids (FAA) biochemical agent. It showed that the mortality rate of J2 juveniles was more than 80% and suppression rate of egg hatching was 74% at 1/50 concentrations of FAA. As a result of conducting a tomato pot culture experiment for 60 days after treating 1/50 concentrations of FAA biochemical agent in rhizosphere soil, it showed that the control effects were 63% of juveniles density in the soil, 59% of egg mass and 61% of root gall index, respectively. Based on the above results, it is considered that the FAA biochemical agent extracted from chicken feathers can be used as an environmentally friendly nematicidal agent of RKN.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.296-300
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• 2005

Among the root colonizing and plant growth promoting bacteria isolated from the bacterial wilt suppressive soil, five strains were detected to produce siderophores by CAS agar assay. The most effective isolate, TS3-7 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 80% reduction of bacterial wilt disease compared with the control. Significant disease suppression by TS3-7 strain was related to the production of siderophore. Besides iron competition, induction of resistance of the host plant with siderophore was suggested to be another mode of action that suppress bacterial wilt, based on the lack of direct antibiosis against pathogen in vitro. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, TS3-7 stain was identified as Pseudomonas sp. TS3-7.